This invention relates generally to connectors for connecting together pairs of terminal posts and more particularly it relates to relatively small connectors for connecting together densely populated pairs of terminal posts, one pair being positioned in a first matrix of a pair of terminal posts, and the other pair being positioned in a second matrix of pairs of terminal posts, with the columns and rows of pairs of terminal posts of the two matrices being interleaved.
In electronic systems, particularly those involving switching or the connecting of one of a plurality of lines to one of a second plurality of lines, matrices are frequently employed. One plurality of lines can be considered parallel to the X axis in a rectangular coordinate system and the other plurality of lines can be considered to be parallel to the Y axis. The most direct way to connect any of the first plurality of lines to any of the second plurality of lines is to make a connection at the intersection of said two lines.
In some applications such connections are relatively temporary, as for example, when one subscriber (a transmitting station) in a telephone system dials a number and thereby makes a connection with a second subscriber (a receiving station) in the system. In other applications the connections at the intersection points of the matrix are more permanent, as for example, when a given subscriber's station is assigned a given dialing number which, when dialed, will energize that particular station.
At the risk of over-simplication assume that a particular station is to be connected to a given line in one of the Y coordinates. By excitation of a predetermined pattern of X lines, the given Y line can be caused to respond thereto to ring the telephone assigned to the said given Y line. To change the dial address of a given telephone station it has been necessary in the past for a technician to manually rewire the X oriented lines to conform to the new dialing address.
To eliminate the relatively lengthy and expensive procedure of manually rewiring the switching equipment, a new system for making such changes in electrical connection has been developed. The new system includes a plurality of terminal posts mounted upon a substrate and arranged in an orderly array so that each terminal post can be located by rectangular coordinate definition. Connector means are employed to connect together predetermined ones of said terminal posts in order to make a connection between an X oriented line and a Y oriented line in the electrical matrix system.
Certain physical problems are present, however, in making the actual connection between an X and a Y line at the point where they physically cross each other, as for example, on opposite sides of a substrate board. Moreover, it is necessary in the telephone art to connect together the terminal posts of two pairs of terminal posts, that is a first post of a first pair of terminal posts must be connected to a first post of a second pair of terminal posts, and the second terminal post of the first pair of posts must be connected to the second post of the second pair of terminal posts in order to complete the connection at a given matrix point. Each X line and each Y line is, in fact, a pair of conductors, thereby necessitating the connecting together of two pairs of terminal posts in order to connect together a given electrical matrix point.
A particular relation between the position of the pairs of terminal posts mounted in the substrate and the pairs of X and Y oriented conductors has been devised to permit a near optimum grouping of connections between pairs of pins on said substrate. Specifically, the pairs of pins are arranged on the substrate in two separate matrices, each consisting of columns and rows which are rotated approximately 45.degree. from the Y and X axes of the electrical matrix determined by the X and Y oriented lines between the pins of the posts mounted on the substrate.
The columns and rows of the two matrices of pairs of pins are both interleaved, with each intersection point of each matrix containing two terminal posts arranged in parallel alignment with the columns. A pair of terminal posts of the first matrix is connected to every other pair of Y oriented lines in the electrical matrix along any given X coordinate on a first side of said substrate, while a pair of terminal posts of the second matrix is connected to every other pair of X oriented lines in the electrical matrix along any given Y coordinate on the second side of said substrate.
Thus, for example, to connect any given Y oriented pair of lines to any given X oriented pair of lines, it is necessary to make a connection between the two terminal posts located at one electrical coordinate intersection point to the two terminal posts located at a second electrical coordinate point, since at no intersection of the electrical matrix system are there terminal posts connected to both X and Y oriented pairs of lines. For the same reason more than one type connector is required in order to connect any given X or Y oriented pair of lines to any given Y or X oriented pair of lines. More specifically, since the pairs of terminal posts connected to the X oriented pairs of lines or to the Y oriented pairs of lines occur only at every other pair of X or Y oriented pairs of lines in the electrical coordinate system, a first connector with a given configuration can connect a given pair of terminal posts connected to a pair of lines of a first electrical orientation to every other pair of lines of the other electrical orientation. Accordingly, a second connector having a second configuration is required to connect said given pair of posts to any of the remaining alternate pairs of lines of said other electrical orientation.
Because of the dense population of terminal posts on a substrate, the physical size of the connectors must be quite small. Accordingly, as much of the available space of the substrate surface as possible should be occupied by the connector housings in order to make the connectors as large as possible for purposes of physical strength and reliability. In fact, it is desirable that the connector housings be configured so that the sidewalls of each connector housing abut against, or are very close to, portions of the sidewalls of the adjacent connector housings.
Furthermore, it is desirable that the two types of connector housings be configured so that they can be located precisely in one of the two matrices of pairs of posts and further, has means thereon by which it can be physically gripped by automated equipment and either removed from a given location on the substrate or alternatively, be installed in any given and available location on the substrate.